Hello, I tried out the demo and I have some thoughts. First of all, the voice acting caught my attention and I started to get invested to it. It was a good start to a demo in my opinion.
In terms of battles, I think the damage needs more "feedback". I'm no expert in action battle, but it doesn't feel 'good' as in some other ARPG like kingdom hearts. Also it feels like enemies have too much HP and the demo feels slow. And overall it feels repetitive in the first few minutes.
And finally the game had a weird bug at door '4' where my party suddenly stand together at a corner and cannot move. It was resolved by changing character.
Hope these help your further development.